Endoglin is Highly Expressed in Human Mast Cells

Abstract

Endoglin, known to be expressed in proliferating vessels, is of worth when evaluating microvessel density as a prognostic factor in many types of malignancies, including some subtypes of leukemia cells. In childhood acute lymphoblastic leukemia, endoglin is associated with adverse outcome. In bone marrow, endoglin identifies the repopulating hematopoietic stem cells. Mast cells are a component of normal tissue and play an important role in the regulation of several processes, including inflammation and neoplasia. The aim of this study was to evaluate the use of endoglin as a biological marker of mast cells compared with the gold standard stains. We studied 15 specimens of neurofibroma, 9 of mastocytosis, and 6 of fibrous scar tissue through immunohistochemistry (for endoglin and mast cell tryptase) and histochemical staining using toluidine blue. Quantitative analysis of the cells was performed by counting 5 hotspots. The validity of endoglin as a mast cell marker was assessed by intraclass correlation coefficient. The Kruskal-Wallis test was used to compare mast cell count for each marker. A strong endoglin expression was found in the cytoplasmic granules of mast cells within the 3 groups. Similar results were observed with mast cell tryptase as well as toluidine blue. The intraclass correlation coefficient revealed that endoglin is a highly reliable biomarker of mast cells when compared with mast cell tryptase and toluidine blue. In conclusion, endoglin may assist in the diagnosis and pathogenesis study of various processes associated with mast cells. An endoglin-neutralizing treatment for solid cancers and leukemia could also affect mastocytes and the immunologic system.

Mast Cells in Human Cutaneous Neurofibromas: Density, Subtypes, and Association with Clinical Features in Neurofibromatosis 1

“…Increased mast cell density in human cNFs has been reported in comparison to normal skin [22‒26]. However, no prior study has examined mast cell subtypes defined by tryptase and chymase expression in human cNFs.…”

Microglial Phenotyping in Neurodegenerative Disease Brains: Identification of Reactive Microglia with an Antibody to Variant of CD105/Endoglin

“…CD105/endoglin is also expressed by certain types of cancer and stem cells [53,54,55,56]. This study is the first to describe staining of microglia in human brains and suggests that it could be a marker for types of activated microglia in tissue.…”

Impact of CD105 Flow-Cytometric Expression on Childhood B-Acute Lymphoblastic Leukemia

“…7 It is expressed on the surface of endothelial cells, stromal cells, melanocytes, and different hematopoietic cells. [8][9][10] It is highly expressed as well on the surface of activated vascular endothelial cells but not or weakly expressed on the normal quiescent vessels. Therefore, it has been proposed as a marker of angiogenesis.…”